Image:1osl ca.pdb

1osl.pdb (20 models) with all ATOM records deleted, except for alpha carbons and phosphorus atoms. Header deleted, except that secondary structure (HELIX) records were retained. Gzipped. This reduced the uncompressed file from about 5 megabytes to about a quarter megabyte (~20 fold); the compressed file is 43K. Jmol memory was frequently inadequate for the original 1osl.pdb.